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exhaust backfire


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okay, I've got an '84 GL, 4x4, 4 speed trans. runs great. hitachi 2v is rebuilt, wires, cap rotor, timing (11 btdc), valve adjustment etc etc all in great shape.

the only problem is an exhaust backfire in between shifts, or just letting off the gas all of a sudden after I've been "getting on it".

sometimes just like a little burble, but the majority of the time, it's like I shot a 9mm.

it's so bad, my muffler has actually expanded because of it.

if I shift fast enough, I can get to the next gear before she bangs (the tranny synchros hate me)

my book says something about an "anti-afterburner valve" but I can't find one, or even more info about it.

any ideas there?

thanks for reading!

Dan

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Fix the exhaust leaks in your y-pipe, and block the air suction valve steel tubes with quarters.

 

GD

 

+1 this is the same thing I had going on with mine too, if you have welded on your exaust and it isnt welded up all the way, what will cause it too...

 

Jeff

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I have welded on my pipes. I torched a hole in the top of the Y in order to yank the catalyst out, then patched it. but, it is tight. no telltale signs of leakage at all, from front to back.

 

but, I am gonna plug those suction valve pipes and see where that gets me.

 

I sure appreciate the feedback!:)

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wherever you can squeeze them into the rubber line, is where I figured they should go. drivers side, it' the rubber line at the air cleaner. passenger side, it's closer to the pipes (take the tire out). i don't have pics, but you really shouldn't need 'em. just keep air from flowin through the lines.

 

best $.50 I've ever spent

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